The udev(7) man page states:
RUN
...
This can only be used for very short-running foreground tasks. Running
an event process for a long period of time may block all further
events for this or a dependent device.
Starting daemons or other long-running processes is not appropriate
for udev; the forked processes, detached or not, will be
unconditionally killed after the event handling has finished.
ceph-disk activate is far from a short-running task:
- check whether path is a block dev, for dirs call through to
activate_dir()
- call blkid to obtain the filesystem type for the block dev
- pull mount options from hard-coded ceph.conf file
- mount the OSD dev at a temporary path
- check the ceph magic for mounted filesystem
- read cluster uuid and locate corresponding /etc/ceph/{cluster}.conf
path
- read or generate (if missing) the OSD uuid
- create a file indicating init system usage (systemd)
- mount the device at a second (final) location
- umount (lazy) the temporary mount path
- enable the systemd ceph-osd@{osd_id} service
- start the systemd ceph-osd@{osd_id} service
This logic is therefore best left in a systemd service for execution. As
it is less limited in terms of execution time, and also allows for
improved event handling in future (fsck, dmcrypt mapping etc.).
This change sees 95-ceph-osd.rules.systemd trigger ceph-disk activate or
ceph-disk activate-journal via new ceph-disk-activate-journal@.service,
ceph-disk-activate@.service and ceph-disk-dmcrypt-activate@.service
systemd service files.
ceph-disk-dmcrypt-activate@.service makes use of the newly added
--dmcrypt parameter for ceph-disk activate.
Signed-off-by: David Disseldorp <ddiss@suse.de>
